1. Field of the Invention
The present invention relates to a glass cullet separation apparatus, and more specifically to an apparatus for separating, by colors, ordinary glass cullet (broken glass) of glass bottles etc. to be recycled and for separating foreign glass cullet of heat resisting glass etc. which is commingled therein.
2. Description of the Prior Art
Recycling of used bottles and the like is currently taking place, wherein, except those reusable bottles such as for beer and other alcoholic drinks, collected bottles are broken by a crusher into cullet of several tens mm size (dust glass), melted and made use of as recycled products.
The glass bottles to be recycled are required to be separated into transparent glass and each colored glass according to purpose of use but at the stage of collecting and crushing, various kinds of colored glass and unnecessary foreign matter are mingled together. In some cases, there is commingled a heat resistant glass which has a higher melting temperature than ordinary glass so as not to be melted at the time of recycling.
In order to separate or remove such cullet having various colors commingled therein and foreign matter, there is used a conventional apparatus wherein, while crushed cullet is being conveyed by a conveyor etc., iron scraps are removed by a magnet, aluminum fractions by a metal detector etc. and removal of earthenware and separation of cullet into each color are performed manually by workers standing aside a conveyor line. On other hand, as to the heat resisting glass, especially in a state of cullet, it is difficult to discriminate the heat resistant glass by color from ordinary glass. If the two glass types are commingled at the collection stage, they are substantially inseparable by manual work. It is therefore a conventional countermeasure that, with respect to cullet separated for recycling, a sampling inspection is carried out on each certain unit quantity or an inspection is carried out on recycled products (bottles etc.), which requires a substantial amount of work and quality control.
On the other hand, Japanese laid-open patent application No. Hei 3-89981 dated Apr. 14, 1991 (Reference Patent 1) discloses, as shown in FIG. 9, an apparatus which achieves mechanization and automatization of the work of separating foreign matter in cullet. The foreign matter is removed by the use of an image receiver (or an optical detector) 81 for detecting materials separated into several courses or an analytical device 83 for discriminating the cullet and the foreign matter and a respective pusher 82. Further, foreign matter in the cullet material, fed from a hopper 84 and conveyed by a slide table 85, is detected by a light source 86, the image receiver (or optical detector) 81 and the analytical device 83. The cullet and the foreign matter are separated by the pusher 82 so as to pass on to a non-defective shoot 88 and a foreign matter shoot 87, respectively, and to then be stored in a respective container (not shown).
Also, Japanese laid-open patent application No. Hei 7-132269 dated Jan. 21, 1992 (Reference Patent 2) discloses, as shown in FIG. 10, a method and apparatus for automatically separating cullet according to colors. The cullet is screened by a rotary drum 91 so as to fall on a pallet and arrayed, while being vibrated, in plural rows by an arraying feeder 92 and placed on a separation conveyor 93. Thus, color discrimination is achieved by a color discrimination camera 94 provided on each of the rows and, according to each color so discriminated, the cullet is pushed out on a delivery belt 96 of each color by a push-out member (brush) 95. That is, the apparatus of FIG. 10 is composed of the rotary drum 91 for screening fine particles of the cullet, the arraying feeder 92 provided in plural rows, the separation conveyor 93, the color discrimination camera 94, the push-out member 95 and the delivery belt 96 for delivering the cullet pushed out according to the color thereof.
Further, Japanese laid-open patent application No. Hei 4-16273 dated Jan. 21, 1992 (Reference Patent 3) discloses a color separation apparatus for cullet which, as shown in FIG. 11, includes a rotary type dimensional classification with respect to cullet groups classified in sizes by a rotary type dimensional classification device 101, and plural lines of devices. Each line consists of an arraying lane 102, a carrying belt conveyor 103, a first color discrimination conveyor 104, a second color discrimination conveyor 105, a third color discrimination conveyor 106 and a fourth color discrimination conveyor 107. And, downstream of the first to the fourth color discrimination conveyors 104 to 107 there are disposed a color discrimination sensor 108 and a separation device 109 composing a movable slide and a separation shooter 110 for separating the colored glass based on the result of the discrimination.
In conventional color separation and collection of cullet which relies upon manual work, there are problems as follows:
1) Treatment of a large amount of cullet in a short time is impossible because it requires a substantial amount of manual work. PA1 2) If high speed color separation is to be performed, there is a limitation in the manual work as well as a lack of precision in the separation of colors. PA1 3) Work efficiency is low. PA1 4) Work environment is by no means good due to dust etc. PA1 5) For the manual work, a wide work space is necessary and the entire system becomes larger. PA1 6) If heat resistant glass is commingled, discrimination is difficult and separation becomes impossible, which brings about a quality control problem. PA1 1) While the cullet is sliding on the sliding table, discrimination and separation is performed and irregularities in sliding speed occur due to shape, direction, etc. of each cullet (e.g. whether a bottom face is concave or convex) and in order to effect precise color discrimination and separation in view of such irregularity of speed, it is necessary to make a cullet to cullet space wider which results in a lower treatment speed. PA1 2) After each cullet passes the image receiver (or optical detector) and until it passes the pusher, a next cullet cannot pass the image receiver (or optical detector). For example, after a piece of foreign matter passes the image receiver and until it passes the pusher, if a following cullet passes the image receiver, the latter cullet reaches the pusher before the former piece of foreign matter finishes a discharge action and both of them could be pushed out concurrently by the pusher, or biting of the pusher is caused or, if the cullet is the former and the foreign matter is the latter, decision determination regarding the foreign matter may not be effected. Because of the structure, a cullet to cullet space must be made wider, and thus treatment speed becomes lower and treatment precision becomes worse. PA1 3) Due to irregularity of sliding speed according to shape, direction, etc. of cullet as mentioned in 1) above, if a timing miss of push-out etc. occurs, foreign matter may be discharged into the non-defective shoot and the ratio of foreign matter becomes higher. PA1 4) Because discrimination is performed by the image receiver (or optical detector), discrimination and separation of the heat resistant glass cannot be achieved. PA1 1) Treatment speed is low because the separation conveyor is an intermittently moving type in which the cullet to be separated is swept down by the push-out member (brush). PA1 2) Treatment speed is low because the apparatus is of a type in which the cullet is caused to fall on the pallet sporadically one by one. PA1 3) Discrimination is performed by the color discrimination camera, and thus discrimination and separation of the heat resisting glass cannot be achieved. PA1 1) As one discrimination belt conveyor and separation mechanism can perform a separation of one kind only, if the object to be separated includes plural kinds, a multi-stage discrimination conveyor and plural color discrimination devices and separation mechanisms are necessary and thus the apparatus becomes larger and more complicated. PA1 2) As foreign matter is separated first structurally and there is no more discharge shooter for other miscellaneous matter downstream thereof, if a miss occurs in the separation process, the foreign matter will commingle with any of the separated cullet PA1 3) The discrimination is performed by a color discrimination camera, and thus discrimination and separation of heat resistant glass cannot be achieved. PA1 1) a foreign glass discrimination trigger signal obtainable from the first non-contact type photoelectric sensor as a foreign glass discrimination trigger sensor, PA1 2) a color discrimination trigger signal obtainable from the second non-contact type photoelectric sensor as a color discrimination trigger sensor, PA1 3) a foreign glass signal obtainable from the foreign glass discrimination device, PA1 4) a cullet color signal obtainable from the color discrimination device, PA1 5) a belt movement distance pulse signal obtainable from the belt movement amount measuring means, and PA1 6) an electromagnetic valve trigger signal obtainable from the third non-contact type photoelectric sensor as an electromagnetic valve trigger sensor. PA1 (1) The arraying and supplying means for supplying the cullet continuously at a high speed is a rotary feeder for arraying the cullet along a rotary disc and a circumferential wall of the disc by use of a centrifugal force and for delivering the cullet in a tangential direction of the disc from a delivery port provided at the wall. Thereby, continuous and high speed supply of the cullet becomes possible. PA1 (2) The controlling device is constructed so as to start a count of a cullet movement amount upon triggering of the foreign glass discrimination trigger signal and the color discrimination trigger signal, to control the cullet movement amount by use of the belt movement distance pulse signal and to produce, upon the foreign glass discrimination signal and the cullet color discrimination signal, an electromagnetic valve enabling signal for the electromagnetic valve of the air nozzle which corresponds to the foreign glass and the cullet of each color. The electromagnetic valve enabling signal has a time width which takes into account slip of the belt and the cullet based on a reference timing in which the cullet should have reached the electromagnetic valve trigger sensor. Also, an electromagnetic valve opening signal is a logical product of an electromagnetic valve opening enabling signal and the electromagnetic valve trigger signal. Thereby, the cullet flowing at a high speed and the cullet which has a position on the belt that is slightly deviated due to slip with the belt can be accurately ejected from the belt by the air nozzle for each color and thus separation and collection thereof is ensured. PA1 (3) The cullet conveying belt is provided at a drive shaft or a pulley shaft with a means, such as an encoder, for measuring a rotation amount. Thereby, the amount of movement of the cullet, being conveyed by the belt, can be measured. PA1 (4) The collection bins or receptacles are arranged in an order of collection in which the cullet, which makes up a smaller percentage of the total mix, is collected upstream with respect to cullet which represents a larger percentage of the total mix. Thereby, the cullet which represent the smallest percentage of the mix is collected upstream of the other cullet, while the cullet representing the largest percentage of the mix is collected downstream of the other cullet which represent lesser percentages of the mix. Thus, a separation of the cullet can be accurately performed. PA1 (5) The cullet conveying belt is formed at a portion of the belt with a slit (cut-out portion) through which a laser beam, necessary for discriminating foreign glass, and a transmission light (illumination light), necessary for discriminating colors of the cullet, may pass while the cullet is being conveyed. Thereby, while the cullet is being conveyed with a single stage construction, discrimination of the foreign glass and the cullet of each color and separation of many kinds of cullet is possible. PA1 (6) The cullet conveying belt is driven by a servomotor. Thereby, start of jetting, time length of jetting, etc. of the air nozzle can be timed precisely to effect the separation. PA1 (7) In the glass cullet separation apparatus, the particular construction results in the cullet being separated by blowing the cullet from the belt into a bin or receptacle by a separation means which employs air jets etc. and other foreign matter is collected at a terminal end of the conveying belt without the use of a separation means. Thereby, even if there is a failure in the separation, there occurs no degradation of the collection purity in the respective collection bin or receptacle. PA1 (8) In the glass cullet separation apparatus, the particular construction results in discrimination of foreign glass, discrimination of color and plural separations thereof are performed by one line. Also, the plural color discriminations are performed by a single color discrimination device. Thereby, the apparatus can be made more compact.
Further, in prior art Reference Patent 1, the problems are as follows:
In the prior art Reference Patent 2, problems are as follows:
In the prior art Reference Patent 3, problems are as follows:
In the prior art as mentioned above, there are problems in that the separation precision is low and the treatment speed is low, or if the treatment speed is to be increased, plural lines of devices in an increased numbers become necessary with the result that the apparatus becomes larger.